While it can do the simple things that every suoku app can do out there, what it does different is that instead of giving you hints to solve the sudoku, it gives you tools that you can use to solve more easily.

PS: While this is an advertisement, and I registered on the forums to post this, i have been a long time reader of the Daily Sudoku and the forums.
Moderator: Please move the post if this is the wrong place.

Periodically, I review all the iPhone/iTouch sudoku apps. Most of them are copycat programs that are okay for the 'click and giggle' crowd, but don't provide the features that advanced manual solvers want. At the moment there is really only one sudoku app that meets most of those demands.

However, your app, while still not at the level of my preferred app, is an impressive beginning and distinguishes itself from most of the others by being original in a good way and especially, by providing both hilighting and the ability to manually color cells, something that is mandatory for advanced solving and something that only one other app provides.

The Good:
Designing the app more as a frontend for the person who wants to collect puzzles to solve from sudoku websites and who wants to use the app to help manually solve puzzle as opposed to using the app as just another sudoku solver.
The ability to hilight & manual color cells, something that is very well implemented for a first version release.
The provision of a limited browser within the program that allows one to enter the URL for their favorite websites and go to them & return within the program- excellent!
The presentation of the grid is very nicely done and the difficult challenge of making the various options acessible and intuitive is largely met though it could be improved on somewhat.

What Needs Work (in no particular order):
-have an option to not have opening splash screen so one can return immediately to a puzzle.
-in your description of the app, emphasize it's real strength, which is the use as a frontend with the hilighting & manual coloring of cells and the ability to collect puzzles using the built-in 'browser', instead of emphasizing the ability to randomize puzzles. While the latter is a nice feature, it is only a minor one, all things considered.
-if you manually color cells and exit the program, when you return the coloring is gone, (though the hilighting is still present)- I think that's a bug and it makes it difficult to remember what you were looking for when you left the puzzle.
-the Manual is full of typos- missing letters, reversed letters and missing words and sometimes confusing sentence structure. Some of the latter may be understandable for a first version, but there's no excuse for that many obvious typos.
-when you first open a puzzle, you have the ability to Save it, but I have no clue how to Load that puzzle later on- ie. cannot find any option to Load a Saved puzzle.
-the menu of sudokus to play is confusing. If the idea is for users to play sudokus they have collected and named, then the emphasis should be on their being able to collected them, name them and play them whenever they want. The way it is now, one just gets a menu of various randomized puzzles of varying difficulty level and it is very unclear how to play puzzles one has collected.
-the 2 Libraries are nice, but providing the Library of the most difficult puzzles is of limited value for an app like this. I would suggest more puzzles in the Moderately Difficult, Diabolical, Extreme level.
-I'm surprised that more current sites were not listed in the 'Learning' List from which to select sudokus rather than 3 URLs for the Sudocue site which has long since stopped offering new puzzles. Also, it would be nice to be able to edit one's entries here. It's tedious entering long URLs and if you enter one incorrectly, the only way you'll find out is when you try to go to that site. Without being able to edit, you have to delete your entry and enter it all over again!

However, if it is not clear, I like many things about your app and it already provides better features than most of the others, but many people will not recognize that if you don't emphasize the differences in your description. It has every possibility of being a very top sudoku app with a little more work. If you'd like any help with suggestions feel free to PM me.

I really enjoy playing Sudoku on my iphone. the one problem I have found is that with the apps I have tried you are not able to save the puzzle and come back to it later. Are there any good ones that comeone can recomend that you are able to save. Thanks